From: Daniel Vetter <daniel@ffwll.ch>
To: Heinrich Schuchardt <xypron.glpk@gmx.de>
Cc: David Airlie <airlied@linux.ie>,
linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org
Subject: Re: [PATCH 1/1] drm: avoid exposing kernel stack in compat_drm_getstats
Date: Mon, 22 Aug 2016 09:27:18 +0200 [thread overview]
Message-ID: <20160822072718.GC6232@phenom.ffwll.local> (raw)
In-Reply-To: <1471802179-2886-1-git-send-email-xypron.glpk@gmx.de>
On Sun, Aug 21, 2016 at 07:56:19PM +0200, Heinrich Schuchardt wrote:
> The C standard does not specify the size of the integer used
> to store an enum. Hence in structure drm_stats32_t alignment
> bytes may exist.
>
> To avoid exposing bytes from the kernel stack it is
> necessary to initialize variable s32 completely.
>
> Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Applied to drm-misc, thanks.
-Daniel
> ---
> drivers/gpu/drm/drm_ioc32.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/gpu/drm/drm_ioc32.c b/drivers/gpu/drm/drm_ioc32.c
> index 57676f8..32a489b 100644
> --- a/drivers/gpu/drm/drm_ioc32.c
> +++ b/drivers/gpu/drm/drm_ioc32.c
> @@ -346,6 +346,7 @@ static int compat_drm_getstats(struct file *file, unsigned int cmd,
> struct drm_stats __user *stats;
> int i, err;
>
> + memset(&s32, 0, sizeof(drm_stats32_t));
> stats = compat_alloc_user_space(sizeof(*stats));
> if (!stats)
> return -EFAULT;
> --
> 2.1.4
>
> _______________________________________________
> dri-devel mailing list
> dri-devel@lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel
--
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch
next prev parent reply other threads:[~2016-08-22 7:27 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-08-21 17:56 [PATCH 1/1] drm: avoid exposing kernel stack in compat_drm_getstats Heinrich Schuchardt
2016-08-22 7:27 ` Daniel Vetter [this message]
2016-08-22 8:29 ` Jani Nikula
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